Connecting of metal parts



March 29, 1938. 5, gw s CONNECTING OF METAL PARTS Filed Jan. 2, 1935 2 Sheets-Sheet l .Ziivezzz I (file Luis r, w

March 29, 1938. G. s. LEWIS CONNECTING OF METAL PARTS Filed Jan. 2, 1955 2 Sheets-Sheet 2 MN @N 6 ir gjrzz ar/ or e 63055,

N Lfi g y w Patented Mar. 2 9, 19 38 7 PATENT OFFICE CONNECTING F METAL PARTS George S. Lewis, Oak Park, Ill., assignor to Battery Patents Corporation, Chicago, 111., a corporation of Illinois Application January 72,1935, Serial No. 155

4 Claims.

. This invention relates to the connecting of metal parts and more particularly to methods of connecting tubes to metal members and to the products so formed.

An object of the invention is to provide methods for connecting tubes to metal members in simple and extremely sturdy construction. A further object is to provide methods of connecting metal members through the flaring of the, end of one no of the members within a recess afforded by the other member. A further object is to unite aluminum or magnesium alloys in bicycle frames and other frame constructions. objects and advantages will appear as the specifii's cation proceeds.

The invention is illustrated, in preferred embodiments, by the accompanying drawings, in which- Figure l is a broken sectional view showing the seat post of a bicycle in the first operation of being joined to the mast; Fig. 2, a view similar to Fig. 1, but showing the connecting operation completed; Fig. 3, a broken sectional view showing a tube connected to the head casting of a bicycle in accordance with my invention; Fig. 4, a broken sectional view showing a tube being connected to the head casting of a bicycle; and Fig. 5, a view similar to Fig. 4 but showing the connecting operation completed.

30 e In the illustration given in Figs. 1 and 2, a seat post casting ll) of duralumin or other aluminum or magnesium alloy is provided with a recess II and with a circular extension [2 received within the mast IS. The inner wall of the recess II is 35 preferably inclined orcurved as indicated by the numeral 14. If. desired, the tubular extension I2 may be provided with an annular groove I5.

In the first operation shown in Fig. 1, the tube is forced inwardly under pressure against the in- 40 clined wall l4 so as to flare the ends iii of the tube; or, alternately. the end of the tube may be flared on some tool prior to its being placed within the recess.

In the second step of the operation, as shown 45 in Fig. 2, the annular flange I1 is spun inwardly about the flared ends Hi to form a rigid connection. If desired, the portion l8 may be spun into the groove l either in the first or second step of the operation.

50 In the construction shown in Fig. 3, the head I9 is provided with an integral extension substantially the same as that provided by the seat post l0, and the method of connecting thetube 2| thereto is the same as described in connection 5 with Figs. 1 and 2.

Other specific In the modification shown in Figs. 4 and 5, the head is equipped with a tubular extension 22 which is provided interiorly with an annular recess 23 adjacent a shoulder 24. The tube 25 is provided at its inner end with a thimble or hollow plug 26 having a tapered or outwardly flared end 21. The inner closed end 28 of the thimble is dished rearwardly and adjacent the convex end, the thimble is provided with threads or serrations 29. 10

In the operation of the device, the thimble is placedin the end of the tube, as illustrated in Fig. 4, and the tubewith the thimble is inserted within the tubular extension 22 until the flared end 21 of the thimble engages the inwardly ex- 15 tending shoulder 24. The pressure upon the tube is continued and increased so as to fiare the end of the tube as shown in Fig. 5. In the latter operation, the end of the tube follows the tapered or inclined wall 21 of the thimble. In this manner, the tube is securely locked within the recess 23 of the extension 22. 'The thimble may be additionally locked by extending a rod through the other end of the tube and straightening the convex wall 28, as shown in Fig. 5, thus forcing the serrations or roughened surface 29 into the inner wall.

While in the illustrations, I have shown the plug or thimble as hollow, it will be understood that a solid plug may be employed, and the shape 30 of the plug may vary considerably just so long as it provides an inclined or taperedwall for forcing the tube into the locking recess.

The foregoing methods have been found particularly adaptable for use with tubes and castings of aluminum alloy, such as duralumin and other similar alloys, such as magnesium alloy. The duralumin tube flares under pressure and is guided by the thimble or tapered plug into the locking recesses. The thimble or plug 26 may be made of steel or other suitable metal.

While I have described the invention particularly in connection with the assembling of hicycle frames i'rom duralumin or aluminum alloy parts, it will be understood that the invention extends to other forms of construction and to other types of metal. While duralumin and the other metals mentioned lend themselves with a high degree of success to the methods described,

. it is obvious that the invention may be employed in connection with other metals and other frames. The foregoing detailed description has been given for clearness of understanding only, and no unnecessary limitations should be understood therefrom, but the appended claims should be construed as broadly as permissible, in view oi the prior art.

I claim:

1. The method of connecting a tube to a member equipped with a'tubular extension comprising: providing said tubular extension interiorly with a locking recess having a shoulder adjacent thereto. inserting a plug within an end oi! said tube, said plug having an outwardly tapering portion extending outside oi said tube. and pressing said tube and plug into said tubular extension so that the flared end of said plug engages said shoulder, and continuing to press said tube inwardly to cause the end-edge thereof to flare outwardly through engagement with the flared end oi. said plug into said locking recess.

2. The method or connecting a tube to a member provided with a tubular portion comprising: providing said tubular portion interiorly with an annular recess having a shoulder adiacent thereto, inserting a thimble provided with a flared end into said tube, pressing said tube and thimble inwardly to bring the flared end thereof into engagement with said shoulder. continuing the pressure exerted on said tube to flare the end thereof 7 into said recess, said thimble being provided with a rear convex wall adapted to be straightened to exert pressure against the interior of said tube. 3. The invention of claim 2 in which the rear peripheral portion of the thimble is provided with serrations adapted to be pressed into the metal oi the tube.

4. The method of connecting a tube to a member equipped with a tubular portion comprising: providing said tubular portion interiorly with an outwardlyflared tubular recess equipped with a shoulder adjacent the inner end of said recess, inserting a plug within the end of said tube, said plug having an outwardly flared end portion adapted to engage said shoulder and pressing said tube and plug inwardly against said shoulder so as to flare the end-edge of saidtube outwardly into said annular recess.

GEORGE S. LEWIS. 

